1. Field of Invention
This invention relates to a cell therapy method and a composition for transplantation of beta-islet cells isolated and cultured from animal pancreases to promote natural insulin production among people with diabetes.
2. Description of Related Art
Type 1 diabetes affects more than one million Americans. Type 1 diabetes is the most severe form of the disease, in which the body's immune system attacks insulin-producing cells required to keep blood sugar at normal levels. It is known that extremely low blood sugar can result in seizures, impaired cognition, or unconsciousness. In the most severe cases, the complications are not well controlled by insulin.
Ideally, replacing insulin-producing cells in the pancreas can free diabetics from lifelong insulin injections and effectively cure the disease. The transplantation of these “islet” cells can now be done in two ways, through a whole pancreas transplant or through a less invasive and less costly process of injecting just the islet cells. Successful pancreas transplantation has been demonstrated to be effective in significantly improving the quality of life of people with diabetes, primarily by eliminating the need for exogenous insulin and frequent daily blood glucose measurements (Pancreas Transplantation for Patients with Type 1 Diabetes. Diabetes Care. 25 (Supplement 1): S111. January 2002). However, pancreas transplants require lifelong immunosuppression therapy to prevent rejection of the graft and potential recurrence of the autoimmune process that may destroy pancreatic islet cells.
The transplantation of beta-islet cells from donor pancreases has been shown to promote natural insulin production among patients with type 1 and type 2 diabetes (see Sperling, M. A. Type 1 Diabetes: Etiology and Treatment. Totowa, N.J.: Humana Press Inc. 2003. p. 529-552; Insulin Therapy. In: Edelman, S. V. and Henry, R. R. Diagnosis and Management of Type 2 Diabetes. Caddo, Okla.: Professional Communications, Inc. 2002. p. 121-148). Islet cell transplantation can be performed as a percutaneous minimally invasive procedure, in which islet cells are infused into the liver via the portal vein. However, like other transplant patients, islet recipients must take immune-suppressing drugs to prevent rejection of the foreign cells.
Xenografts or xenotransplants of islet cells derived from pork or beef has been studied and shown as required immunosuppression.
Ability of pre-cultured beta-cells of pancreases of newly-born rabbits to survive and to actively function in organism of xenogeneic recipient was demonstrated by us in experiments on rats with experimentally induced Diabetes Mellitus. (Skaletsky N. N. and others. 1994 {4}). Expressed and long-term (8 weeks—experiment term) anti-diabetic effect of xnotransplantation of cultures of islet cells as in cases of administering into abdominal cavity and spleen, and also in cases of administering it into transverse abdominal muscle. After experiments, histological tests were conducted that at the place of introduction of xenotransplants discovered islet cells with preserved structure and without signs of cellular immune reaction. At the same time, clear signs of regeneration of own beta-cells in pancreases of animals-recipients were detected. Beside a well-defined sugar-reducing effect, a well-defined medical-prophylactics effect of xenotransplantation of islet cells cultures on distinctive late complication f diabetes—Nephropathy,—was noted during experiments (Skaletskaya G. N. and others (2005 {4}).
RU 2135193 to Skaletsky at al. discloses obtaining beta islet cells from new-born rabbit pancreas and to transplantation methods. Beta cells are obtained by migration from pancreatic fragments in a culturing method requiring addition of serum to a culture medium.
Thus, despite of current developments, islet cells from different sources which would not require immunosuppression are needed.
All references cited herein are incorporated herein by reference in their entireties.